“In the movie Contagion, I played an epidemiologist trying to stop the spread of a hypothetical virus. To prepare for the role, I spent time with some of the best public health professionals in the world,” Winslet says.

“And what was one of the most important things they taught me?” she continues. “Wash your hands like your life depends on it because right now, in particular, it just might. Or the life of someone you love, or even the life of someone you might not know but is still deserving of your consideration. Like the people on the front lines of this fight right now, the doctors and the healthcare providers, the people who are still working in the grocery stores or delivering food to your homes, which is where you should be right now.”

The PSAs were written under the guidance of the same experts who worked on the film—the college’s Dr. Larry Brilliant, Mark Smolinski, Laurie Garrett and Dr. W. Ian Lipkin, the latter of whom revealed on Tuesday that he has contracted the virus, or COVID-19, which has infected more than 590,000 people worldwide.

In his PSA, Damon talks about the importance of social distancing.

“It means stay six feet away from another person,” he says. “It means not gathering in groups and it means staying home or sheltering in place, if that’s what government officials are telling you to do. People can have COVID-19 and have very mild symptoms or no symptoms at all. So even if you think that they’re healthy, or you think that you’re healthy, don’t take that chance. It is not worth it.”

Contagion cast member Laurence Fishburne also talks about the same preventative tactics, and also offers some words of hope.

“I know it’s frightening to wake up every day and to see on the news that more people have died,” he says. “But the overwhelming majority of us are going to live. Every day the number of those who are being cured will increase and our scientists can learn from how their immune systems defeated the virus and discover treatments until we have a vaccine.”

“So until we have a cure, you can be that, for the people where you live and for the people that you love,” he says. “We can beat this thing together just by staying apart.”

Cast member Jennifer Ehle says in her PSA, “I’m not a scientist, I’m an actor. I’m also a daughter, a wife and a mother. I realize that this virus is a threat to all of us and so I am hoping we can learn not to be a threat to each other.”

Watch NBC News Special Report: Coronavirus Pandemic Tuesdays at 10 p.m. ET/7 p.m. PT on NBC, MSNBC and NBC News NOW. For the latest updates on the coronavirus pandemic and for tips on how to prevent the spread of COVID-19, please visit The Center for Disease Control and Prevention at https://www.cdc.gov.